1. Field of the Invention
The present invention relates to a digital television receiver, and more particularly, to a digital television signal for receiving program and system information protocol (PSIP) data, a method for processing the digital television signal, and a digital television receiver. Although the present invention is suitable for a wide scope of applications, it is particularly suitable for providing users with a wider range of broadcast program rating options regardless of the location of the digital television receiver.
2. Discussion of the Related Art
Generally, a digital broadcast system refers to a system that uses a specific compression algorithm, such as a hybrid encoding algorithm, in order to compress and transmit digital video and audio data and that recovers the compressed and transmitted video and audio data back to their initial state, so as to provide diverse information to the viewers. The transmitted data that is included in the digital television signal includes the above-described compression encoded video and audio data. The transmitted data further includes diverse control data for managing and controlling operations of the digital television signal.
More specifically, the digital television signal provided in the digital broadcast system broadly includes two types of data: broadcast program data and program and system information protocol (PSIP) data. For example, the program data refers to a television program which a television network company provides to its subscribed viewers. Such program data includes various types of data including video data, audio data, caption data, and so on. The PSIP data includes modulation type, carrier frequency, packet identification (ID) information for demultiplexing the video and audio data from a packet stream that is transmitted in a carrier signal channel, program guide information (i.e., information including program title, program starting time, brief additional information, etc.), caption service, program rating, present time information, and so on, for each channel in order to normally receive the channel for each broadcast program.
Therefore, when a specific digital broadcast channel is selected, the digital television receiver is tuned to the corresponding broadcast channel. Then, the digital television receiver separates the PSIP data from the packet stream, which is stored in an internal memory. Then, the digital television receiver demultiplexes the video and audio data by using the stored PSIP data. Furthermore, the digital television receiver uses a plurality of information table included in the PSIP data, so as to provide the users with a program guidance service providing brief additional information on the TV broadcast program, presence of a caption service, program rating, and schedule of the corresponding TV broadcast program.
More specifically, according to the digital broadcast system standards, a PSIP data table which is inserted in the digital television signal and transmitted therethrough includes rating region table (RRT) data. Herein, the RRT data includes information corresponding to the region code used in a rating system (RS), region name, number of RS used in the corresponding region, name of each RS, and so on. In other words, the RRT indicates rating information of a broadcast program corresponding to multiple geographical rating regions. For example, in a digital television receiver used in the United States (US), when broadcast programs that can be viewed by viewers over age 14 (i.e., Parental Guidance (PG-13) rated programs) are blocked, the programs corresponding to this rating are not outputted to the screen of the receiver.
However, the related art method of using the RRT data for setting up ratings for digital broadcast programs has the following problems. In the related art method, the program ratings are defined by regions, and the related art RRT only includes a fixed set of data. Therefore, as a wider range of digital broadcast programs are being newly produced, there are limitations in categorizing the programs based only on a fixed set of rating standards. Furthermore, if the contents of the RRT are decided based on the current geographical rating regions in which the digital television receiver is used, the RRT pre-programmed in the memory of the digital television receiver can no longer be used once the receiver is moved to a different region.